Charles Bolden, NASA administrator, answers a question during a news conference at NASA's Johnson Space Center on Monday, Jan. 26, 2015, in Houston. NASA, Boeing and SpaceX discussed commercial crew development and test plans for launching American astronauts from the United States by 2017. ( Brett Coomer / Houston Chronicle )

Photo: Brett Coomer, Staff

If Russia stops flying U.S. astronauts to the International Space Station, the U.S., lacking a backup plan, would have no choice but to abandon the multibillion dollar outpost to its own fate, NASA Administrator Charles Bolden said Wednesday.

"We would make an orderly evacuation," Bolden said during a U.S. House Appropriations subcommittee hearing.

Because both countries are dependent upon one another - NASA funds most station operations, and provides electricity and other services, while Russia provides transport and propulsion - the $140 billion station would be lost.

It was a frank admission from Bolden, who has sought to sidestep the question during the last year as diplomatic relations between the U.S. and its partner in space have deteriorated over Russian aggression in Ukraine.

Bolden has maintained that NASA and Roscosmos, its counterpart agency in Russia, have a cordial working relationship and that so far Russia has kept its commitments to NASA.

His comments came during a tense 10-minute showdown with the space and science subcommittee's new chairman, John Culberson.

The Houston Republican, comparing Russia President Vladimir Putin to the country's former dictator, Josef Stalin, pressed Bolden several times on whether the agency had a contingency plan before finally getting a direct answer.

"You are forcing me into this answer, and I like to give you real answers," Bolden finally said. "I don't want to try and BS anybody."

When he became NASA's administrator in 2009, Bolden, a four-time astronaut, was faced with the imminent end of the space shuttle program, a decision endorsed by both former President George W. Bush and his successor, President Barack Obama.

At the time U.S.-Russian relations were less frosty than they are now, and after more than a decade of working extensively with Roscosmos, NASA decided it could rely on Russia's Soyuz spacecraft to reach the orbiting laboratory, which was largely built and funded by the U.S.

Life without a shuttle

NASA planned to end this reliance on Russia by paying commercial companies to build American transport options, and Boeing and SpaceX are doing just that, but neither will be ready to fly astronauts until at least 2017.

Then, last year, Russia invaded Crimea and began agitating in eastern Ukraine. Russia's deputy prime minister over the country's space program, Dmitry Rogozin, said America might need to use a trampoline to get its astronauts into space.

That prompted some longtime space officials, including legendary flight director Chris Kraft, to say the space shuttle never should have been ended without a replacement in hand.

"The cancellation of the space shuttle may be the biggest blunder ever made by the United States," Kraft said at the time.

Despite the Ukraine issues and Rogozin's rhetoric, NASA astronauts have continued to fly regularly on the Soyuz. Even now astronaut Scott Kelly is in Russia preparing to launch for his year-long space station mission later this month.

But during Wednesday's hearing on NASA's budget, Culberson, citing concerns about recent events in the Ukraine and Russia, pressed Bolden on whether NASA has made any contingency plans within the last year if the situation continues to worsen.

"We need to know, what is your plan in the event the Russians say they're not flying Americans to the space station any more?" Culberson asked. "Please answer that directly."

So Bolden did.

"Our backup plan, if you want to talk about that, would be to mutually agree that the space station and space exploration is going to come to an end," Bolden said. "We would make an orderly evacuation of the International Space Station."

During an interview after the hearing, Culberson expressed concern that NASA hasn't scrambled enough during the last year to more quickly develop options if Putin decides to play hardball in space.

Didn't get full funding

"It is appalling, isn't it?" he said. "It's deeply disappointing and distressing to see that the world's greatest space agency has no backup plan to get Americans to the space station if the Russians abandon us. It's unacceptable that their only solution is to abandon the high ground. It shows how far the space program has fallen under the Obama administration."

Bolden, however, insisted NASA had no other options.

At present, only Russia, with its Soyuz spacecraft, and China, with its Shenzhou spacecraft, have the capability of flying humans into space. Congress has barred NASA from working with China.

NASA's only choice is to work with Russia until the commercial space alternatives it is funding -Boeing's CST-100 and SpaceX's Dragon - are ready in 2017.

Bolden also noted during the hearing that those private spacecraft could have been ready later this year if Congress had fully funded the commercial crew program, as Obama sought.

"I came to this committee, and I said it over and over," Bolden said Wednesday.

"Had we gotten the funding we requested when I first became NASA administrator, we would have all been joyously going down to the Kennedy Space Center later this year to watch the first launch of some commercial spacecraft with our crew members on it. But that day passed."